1. Field of the Invention
The invention relates generally to electronic device manufacturing and more particularly to techniques for providing shielding for electronic components.
2. Related Art
Portable electronic devices such as cell phones typically utilize electronic modules to provide a high level of functionality in a small package. The electronic module can include, for example, any combination of one or more integrated circuits and one or more passive devices such as resistors, capacitors, and inductors mounted on a module circuit board. The components of the electronic module can be encapsulated using a non-conductive material to form an overmolded electronic module package. Electronic circuits within an electronic module typically receive, transmit and/or internally utilize time-varying electromagnetic signals. Such electromagnetic signals can radiate through the non-conductive packaging material of the electronic module and affect other electronic devices (e.g., cause interference), exceed regulatory limits, and/or be subject to interception. Also, externally present magnetic energy of either natural or artificial origin may penetrate non-conductive packaging material of an electronic module to adversely affect the circuitry within the electronic module. Accordingly, good engineering practices dictate that electromagnetic shielding be provided to attenuate electromagnetic energy to limit potentially adverse effects. Typically electromagnetic shielding is provided by surrounding the electronic module with a conductive material such as a structure that is stamped or otherwise formed out of a thin sheet of metal. However, such a stamped shield needs to be large enough to avoid mechanically interfering with the electronic module. Moreover, the dimensions of the shield have to be sufficient to accommodate manufacturing tolerances of the electronic module, as well as those of the shield. The additional size required by a stamped shield limits miniaturization of products including such electronic modules. Another disadvantage of a stamped shield is that attaching the shield involves an additional manufacturing step that cannot be performed until after installing the electronic module.
Thus, a technique for providing electromagnetic shielding that avoids such disadvantages is needed.